const  parseSpecifiedUrlParams = (url, key = null) => {
    let offset = url.indexOf("?");
    if (offset !== -1) {
        url = url.substr(offset);
    }
    let pairs;
    let params = {};
    if (url) {
        url = url.substr(1);
        pairs = url.split("&");
        for (let pair of pairs) {
            let list = pair.split("=");
            if (list.length == 2) {
                params[list[0]] = list[1];
            }
        }
    }

    if (key) {
        if (params[key] === undefined) {
            return null;
        } else {
            return params[key];
        }
    } else {
        return params;
    }
}

const parseUrlParams = (key = null) => {
    let search = window.location.search;
    return parseSpecifiedUrlParams(search, key);
}


export {
    parseUrlParams
}
